Please select the eligibility criteria that correspond to the clinical trial below.
Title: Supplementation of Vitamin D in Preterm Infants- Monitored Therapy vs Standard Therapy. A Randomized Controlled Trial
Brief Summary: The purpose of this study is to determine wheather the monitored vitamin D (vit D) therapy is safer and more effective than standard therapy in pretrem infants.


Options:
A: Inclusion Criteria:

* Preterm infants born between 24 and 32 weeks of gestation (estimated by ultrasound)
* In born or admitted to the unit within 48hours from birth.
* Randomization within 7 days from birth.
* Parental consent.
* Mothers willing to return for follow up visits.

Exclusion Criteria:

* Preterm delivery \>=33 weeks of gestation or term delivery (estimated by ultrasound).
* Major congenital abnormalities.
* Participation in another trial.
* Severe illness at birth deemed incompatible with survival.
* Congenital HIV infection.
* Total parenteral nutrition \> 14 days.
* Cholestasis
B: Inclusion criteria

* Currently lactating mothers at least 18 years of age
* Willing to continue exclusively breastfeeding their infant throughout the study interval
* The infant is 1-6 months of age at the beginning of the study
* Willing and able to participate in all aspects of the study
* Mother and infant are in good health, as determined by the study investigator
* Have been provided with, understand, and have signed the informed consent for themselves and their child.

Exclusion criteria

* Have recently travelled (within the preceding 30 days) or plan to travel south of 35 degrees north latitude during the study interval
* Have recently or plan to engage in indoor tanning
* Are currently taking medications that affect vitamin D metabolism, like steroids, anticonvulsants, or barbiturates
* Are nursing multiple infants (e.g. twins)
* Are taking greater than the daily recommended intake of 1000 mg elemental calcium as calcium supplements
* Are taking greater than the standard daily dose of 400 IU of vitamin D found in prenatal vitamins
* Infant weight below 1.67 kg
* Mothers with baseline 25(OH)D levels \>70 ng/ml, and/or infants with baseline 25(OH)D levels \>70 ng/ml
* History of kidney stones
C: Inclusion Criteria:

* 13-19 y old
* between 23 and 29 wk of gestation
* primiparous
* carrying single fetus
* intending to exclusively or predominantly breastfeed

Exclusion Criteria:

* chronic health problems
* smokers
* users of nutritional supplements, except iron supplements provided during standard prenatal care
D: Inclusion Criteria:

* Women between 18-42 years of age
* within 18 plus/minus 3 weeks gestation
* planning to breastfeed their infant
* a singleton pregnancy

Exclusion Criteria:

* Any co-morbid condition such pre-gestational diabetes, TB, cardiac or renal disease, HIV/AIDS, chronic hypertension, inflammatory bowel disease, autoimmune disease, liver disease, or epilepsy; conditions associated with vitamin D malabsorption: celiac disease, gastric bypass;
* History of previous adverse pregnancy outcome \[preterm delivery \<37; weeks GA, stillbirth, severe pre-eclampsia, eclampsia, HELLP syndrome (hemolytic anemia, elevated liver enzymes, and low platelet count)\];
* Women will also be ineligible if they are taking more than 10 µg day supplemental vitamin D or drugs known to interfere with vitamin D metabolism (i.e corticosteroids).

Answer: A