Only mydriatic action is by-
Ans. is 'c' i.e., Phenylepherine Phenylepherine is used as a mydriatic when cycloplegia is not required. It reduces the i.o.t. by constricting ciliary body blood vessels. It is also used as a nasal decongesent. About other options o Tropicamide, homatropine and cyclopentolate are mydriatic as well as cycloplegic.
Tropicamide
Homatropine
Phenylephrine
Cyclopentolate