During witch phase is the least % of the light that hits the moon visible from earth

A new moon

B waxing gibbous

C waning crescent

D full moon

The answer is new moon.

The new moon phase happens when the sun, moon and earth align such that the illuminated half of the moon opposes the earth.

The opposite happens at the full moon phase, when the moon is at its brightest. The other phases are intermediary.