To my mind the correct answer is (A).
"Many Americans travel to Costa Rica during the winter months, the peak season, because of the warmer temperatures found at many of Costa Rica’s tropical beaches and lush rain forests. "
In this sentence, the author decides to add additional information through an APPOSITIVE PHRASE. If the writer decides to delete "the peak season" from the sentence, the meaning of the sentence will remain.
<span>The three types of formal messages are: upward, downward and lateral. </span><span>An informal grapevine message is a common type of message at an organization. This happens when information is shared word of mouth from employee to employee in an unofficial manner.</span>
<span>a neurological disorder marked by sudden recurrent episodes of sensory disturbance, loss of consciousness, or convulsions, associated with abnormal electrical activity in the brain.</span>
