E.
Small recap about Even & ODD :
#1 O+O= E (Whenever there are an even number of odd integers, the sum of the corresponding integers is Even- Always)
#2 O+O+O=O (Whenever there are an odd number of odd integers, the sum of the corresponding integers is ODD- Always)
#3 E+E= E
E+E+E= E
(Whenever there are even/odd numbers of even integers, the sum of the corresponding integers is Even- Always)
Approach :
What we can infer from above? If we have an odd number of integers as odd, then the sum of those integers definitely be ODD.
1. 0 even integers=> 5 odd integers=> sum of a,b,c,d,e = ODD. Possibility
2. 2 even integers=> 3 odd integers=> sum of 3 odd integers (refer #2 above) + sum of 2 even integers( refer #3 above) = ODD. Possibility
3. 4 even integers=> 1 odd integer=> sum of 1 odd integer (refer #2 above) + sum of 4 even integers( refer #3 above) = ODD. Possibility
Thus, all three are possible. Hence E.
Hit Kudos, If you love logic and like simple approaches