B

Step 1: Understand the concept of contact angle. The contact angle is the angle formed between the tangent to the liquid surface and the solid surface at the point of contact.
Step 2: Recognize that for a liquid to spread on a surface, the contact angle must be acute (less than 90 degrees).
Step 3: In the case of mercury on glass, mercury has a high surface tension and does not wet glass, resulting in a contact angle greater than 90 degrees (obtuse angle).
Step 4: Since mercury does not spread on glass, it must exhibit a contact angle that is obtuse, confirming that Option B is the correct answer.
Therefore, the correct answer is B.