The correct option is C watches
'Most evenings' in the sentence indicates that it is a general habit. Simple present tense form of the verb will be used here.
"Watches" in option A is correct as it is in simple present tense and is the singular form of verb. Hence, this is in subject verb agreement.
"Is watch" in option B is incorrect as it is ungrammatical.
"Is watching" in option C does not agree with 'most evenings'. Thus, this is incorrect.
As option A is correct, "none of these" in option D is incorrect.