This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Biochemistry
True statement regarding covalent bonds is : 
Select and explain. 
A. Electrons have same spin, B. Electrons have opposite spin, C. They are weak bonds, D. None of the above
B: Electrons have opposite spin
Answer: B: Electrons have opposite spin 
Explanation: B i.e. Electrons have opposite Spin