plz help with super easy question

Answer:
binomial
Step-by-step explanation:
There are 2 terms within the given expression:
Term #1: 5a²b²
Term #2: -ab³
A monomial only has one term. Ex: 3x³
A binomial has two terms. Ex: 3x³ + 3
A trinomial has three terms. Ex: 6x³ + 3x² + 2
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