During the sensitive period, an organism is least affected by environmental stimulation

Samuel, a 75-year-old man, repeatedly wakes up during the night gasping for breath. This happens because he stops breathing while he's asleep. Samuel is most likely suffering from:

A) sleep apnea. B) astigmatism. C) sleepwalking. D) lung collapse.

To reduce the risk her baby will suffer from a variety of birth defects and complications, a pregnant woman should be sure to consume plenty of _________

A) ?folic acid. B) ?melatonin. C) ?ethanol. D) ?thioglycolic acid.