Final answer:
The expression that is a quadratic binomial is c) 3+x²-xy.
Step-by-step explanation:
A quadratic binomial is a polynomial with two terms and the exponent of one of the variables is 2. In this case, the expression has two terms, 3 and x²-xy. The term x²-xy has the variable x raised to the power of 2, making it a quadratic term. Examples of quadratic binomials are x²-2x and 4a²-5a.