If a central atom has four groups attached to it, the geometry about the central atom is: a) triangular. b) linear. c) pyramidal. d) tetrahedral.

d) tetrahedral

Explanation:

Given that the central atom is attached to the four group.

Number of bond pairs = 4

Number of lone pairs = 0

The formula is .

According to VSEPR theory,

The central atom has 4 bond pairs and 0 lone pair. Hybridization is sp³. The geometry is tetrahedral which has an angle of 109.5°.

Methane, posses a tetrahedral geometry as four atoms of hydrogen are attached to the central atom which is carbon.

Hence. D option is correct.

not clear

what is the question here. i think you messed up.