Please select the eligibility criteria that correspond to the clinical trial below.
Title: Long-term Extension, Multicentre, Multi-international Study to Evaluate the Safety and Tolerability of Oral BAY63-2521 (1mg, 1.5 mg, 2.0 mg, 2.5 mg Tid) in Patients With Chronic Thromboembolic Pulmonary Hypertension (CTEPH).
Brief Summary: Patients who have completed the 16 weeks treatment of the CHEST-1 trial (study number 11348) will be asked to participate in this long term extension study with BAY63-2521. The aim of the long term study is to collect additional information to evaluate the safety and tolerability of BAY63-2521. Patients will be treated with open label medication on their individual optimal dose between 0,5 mg - 2,5 mg tid.


Options:
A: Inclusion Criteria:

* Patients who have completed 16 weeks of treatment in the double blind trial CHEST 1

Exclusion Criteria:

* Patients who have an ongoing serious adverse event from CHEST 1 that is assessed as related to BAY63-2521 are not allowed to participate in the extension trial
B: Inclusion Criteria:

* Must have participated and discontinued in the previous PAH placebo controlled study due to clinical worsening on placebo or tadalafil 2.5 mg, 10mg, or 20 mg
* Must have completed Week 16 of the previous PAH study and had either no clinical worsening or became clinically worse at the Week 16 visit on placebo or tadalafil 2.5 mg, 10mg, or 20 mg
* Females who have a negative urine pregnancy test and are willing to use 2 types of birth control
* Be 12 years or older (country specific regulations apply) with parental approval

Exclusion Criteria:

* Participated in the placebo controlled study and had clinical worsening on 40 mg tadalafil
* Have left-sided heart disease
* Have a musculoskeletal disorder that limits being able to get around
* Nitrate use
* Certain current systemic treatments
C: Inclusion Criteria:

1. Signed informed consent prior to initiation of any study-mandated procedures.
2. Males or females ≥ 12 years of age (females of child-bearing potential must have been surgically sterilized or use a reliable method of contraception).
3. Symptomatic patients with the following types of PAH belonging to World Health Organization (WHO) Pulmonary Hypertension Classification Group I:

   * Idiopathic (IPAH)
   * Familial (FPAH)
   * Associated with PAH (APAH):

     * Collagen vascular disease
     * Drugs and toxins
4. Patients naïve to treatment with advanced PAH therapies (i.e., endothelin receptor antagonists (ERAs), phosphodiesterase-5 (PDE-5) inhibitors or prostacyclins) with a right heart catheterization (RHC) showing all of the following:

   * Mean pulmonary arterial pressure (mPAP) ≥ 25 mm Hg
   * Pulmonary capillary wedge pressure (PCWP) ≤ 15 mm Hg or left ventricular end diastolic pressure (LVEDP) ≤ 15 mm Hg when PCWP is not accurately obtained
   * Pulmonary vascular resistance ≥ 3 Wood units
5. 6-MWT distance ≥ 150 meters and \< 360 meters.

Exclusion Criteria:

1. Patients with Pulmonary Hypertension (PH) belonging to WHO Classification Group II-V.
2. Patients with PAH (WHO PH Classification Group I) other than that listed in the Inclusion Criteria.
3. Pregnant and/or nursing.
4. Women of childbearing potential not using a reliable method of contraception.
5. Patients with known human immunodeficiency virus (HIV) infection.
6. Patients with significant vasoreactivity during right heart catheterization (i.e., a fall in mPAP to \< 40 mm Hg with a decrease of ≥ 10 mm Hg and with a normal cardiac index ≥ 2.5 l/min.m\^2).
7. Patients with restrictive lung disease (i.e., total lung capacity (TLC) \< 60% of normal predicted value).
8. Patients with obstructive lung disease (i.e., forced expiratory volume/ forced vital capacity (FEV1/FVC) \< 0.5).
9. Patients with impaired left ventricular function (LVEF \<50%) or diastolic dysfunction.
10. Patients with portal hypertension, cirrhosis, moderate to severe liver impairment (Child-Pugh Class B or C), or liver enzymes (Aspartate aminotransferase (AST) and/or alanine aminotransferase (ALT)) \> 3.0 times the upper limit of normal range.
11. Treatment with glibenclamide (glyburide) and calcineurin inhibitors (cyclosporine A, tacrolimus) sirolimus, everolimus up to 1 week prior to Baseline (Day 1).
12. Patients currently receiving or predicted to require treatment, during the course of the study, with nitrates, protease inhibitors, or alpha-blockers.
13. Patients with a hemoglobin concentration \< 75 % of the lower limit of the normal range or \< 8.5 g/dL.
14. Patients currently receiving or predicted to require treatment with a prostanoid during the course of the study.
15. Patients with systolic blood pressure \< 85 mm Hg.
16. Patients with body weight \< 40 kg.
17. Patients who have received any investigational product within 90 days prior to Baseline.
18. Patients who previously received any advanced therapy for PAH (e.g., ERAs, PDE-5 inhibitors or prostacyclins).
19. Patients with hypersensitivity to sildenafil or any excipients of its formulation.
20. Patients with any contraindication to sildenafil treatment (i.e., nitrates).
21. Patients with any recent medical condition limiting the ability to comply with the study requirements (i.e., stroke, myocardial infarction).
22. Patients with unstable PAH whose disease state would prohibit the completion of study procedures, in the opinion of the investigator.
23. Patients unable to complete a MRI scan (e.g., claustrophobia).
24. Patients with permanent cardiac pacemakers, automatic internal cardioverter defibrillators (AICD's), neurostimulators, hearing aides, and other implanted metallic devices that are contraindicated during a MRI study.
25. Patients with conditions that would interfere with proper cardiac gating during MRI, such as atrial fibrillation or multiple premature ventricular contractions (PVCs)/premature atrial contractions (PACs).
26. Patients with conditions that prevent compliance with the protocol or the ability to adhere to therapy.
D: Inclusion Criteria:

* Participant in Apex 2 high altitude expedition

Exclusion Criteria:

* Previous history of high altitude pulmonary edema

Answer: A