A Fly Decides to Go on Vacation, Gets in an Airplane

Multiple Choice

A fly decides to go on vacation, gets in an airplane, and travels from the west coast of the USA to the east coast of the USA. When the fly gets to the east coast, it experiences jetlag. What is the molecular mechanism by which the fly's circadian clock is shifted?

A) Light-sensing of Cryptochrome causes TIM degradation which increases transcription of period mRNA.
B) Light-sensing of Cryptochrome causes TIM degradation which decreases transcription of period mRNA.
C) Light-sensing of Cryptochrome causes an increase in TIM protein which increases transcription of period mRNA.
D) Light-sensing of Cryptochrome causes a decrease in TIM protein which increases transcription of period mRNA.