In a four strock-engine, the component located between the lobe and the valve stem is called the?

Question

A. margin B. seat C. retainer D. tappet

Answer 1

Uhm ... the coelum?; the centromere?; the genus?; the endoplasmic reticulum?

Dude ... this is the Biology forum.

Answer 2

The correct answer is D.

Answer 3

Some 4 stroke engines use a rotating valve rather than a cam with lobes,  so the question is not even meaningful for all 4 stroke engines.

But where there is a lobe and valve stem, then a tappet.