The main distinguishable characterstic of a binomial heap from a binary heap is that

The main distinguishable characterstic of a binomial heap from a binary heap is that
 
(a) it allows union operations very efficiently
 
(b) it does not allow union operations that could easily be implemented in binary heap
 
(c) the heap structure is not similar to complete binary tree
 
(d) the location of child node is not fixed i.e child nodes could be at level (h-2) or (h-3), where h is height of heap and h>4
 
My enquiry is from Binomial and Fibonacci Heap in portion Heap of Data Structures & Algorithms I
 
I had been asked this question by my school teacher while I was bunking the class.