What is the compound mncl2 called?

Answer is Manganese(ii) chloride

To answer this, you need to know the charges for both Mn and Cl

Mn is in the transition metal category and is unique with having 3 levels of charges

manganese - MN

Manganese(ii) - Mn^2+

Manganese(iii) - Mn^3+

Cl is a nonmetal with the standard charge of Cl^-1

Since you have two charges that don't cancel out, they get switched.

So Cl would receive a positive 2. Because it was a positive 2, we can assume that it starts with Manganese(ii). Then we add chloride to the end of it as it ends with Cl.

the answer is either b or c