Here's why:

* Central atom: Nitrogen (N)

* Number of valence electrons: Nitrogen has 5 valence electrons.

* Number of bonding pairs: Nitrogen forms 3 single bonds with 3 hydrogen atoms (H).

* Number of lone pairs: Nitrogen has one lone pair of electrons.

VSEPR theory: The Valence Shell Electron Pair Repulsion theory predicts that electron pairs around a central atom will arrange themselves to minimize repulsion. This leads to the following:

* The 3 bonding pairs and 1 lone pair around the nitrogen atom will arrange themselves in a tetrahedral shape.

* However, the lone pair occupies more space than the bonding pairs, pushing the hydrogen atoms closer together.

* This results in a distorted tetrahedral shape, specifically a trigonal pyramidal geometry.

Visual representation: Imagine a pyramid with a nitrogen atom at the apex and the three hydrogen atoms at the base. The lone pair on the nitrogen is located above the base of the pyramid.