The given sentence is a conditional sentence with the conjunction, 'if'. The main clause, 'They play football in the evening' is in simple present tense and expresses a habitual action. It means 'They usually play football in the evening'. The 'if clause' in such a conditional sentence should also be in simple present tense.
Option A: The clause, 'If they did not have any homework' is in past tense.
Option B: The clause, 'If they will not have any homework' is in future tense.
Hence, options A and B are incorrect.
Both the options C and D are in simple present tense. However, the verb, 'does not' (or doesn't) is used with a third person singular subject. The subject in the main clause, i.e 'they' is in third person and is plural. Hence, option D is incorrect.
The verb, 'do not' (or don't) is used with a third person plural subject. As the subject (they) in the main clause is in third person and is plural, option C is correct.