You will be given a definition of a task first, then some input of the task.
In this task, you are given a context and four options. Each option is a suggested ending for the context. You should read the context and pick the best ending for the context. Please answer with "A", "B", "C", and "D".

[header] How to use light therapy to sleep better [title] Talk to your physician about light therapy. [step] Many people experience sleep problems and it's important to contact your doctor if you are having trouble sleeping. Your doctor can rule out other possible causes of your insomnia. <sep> (A) Your doctor may be able to recommend the best medical treatment for you. [substeps] When you don't feel like you are sleeping, you may have a sleep anxiety disorder, which can cause sleep problems. (B) If your doctor isn't familiar with light therapy, ask for a referral to a sleep specialist. A medical professional can help you come up with a plan to treat your insomnia using light therapy. (C) Ask your doctor questions including : [substeps] Has it happened before? How often do i sleep? I've been experiencing light therapy for a long time without managing the situation or reacting to the blackout. Has there been changes in my sleep or how does light and dark play a role in my sleep? Am i taking medications? [title] Try sleeping aids. (D) With a successful light therapy regimen, you may be able to fall asleep by 10 am or even earlier. [substeps] Your doctor may also be able to suggest how to adjust your schedule.
Output:
B