Que. 
Let d denote the minimum degree of a vertex in a graph. For all planar graphs on n vertices with d ≥ 3, which one of the following is TRUE?

a. 
In any planar embedding, the number of faces is at least n/2 + 2 
b. 
In any planar embedding, the number of faces is less than n/2 + 2 
c. 
There is a planar embedding in which the number of faces is less than n/2 + 2 
d. 
There is a planar embedding in which the number of faces is at most n/(d+1) 

Answer:In any planar embedding, the number of faces is at least n/2 + 2 