Question

which of the following is a masculine noun?
pluma
cuaderno
maestra
profesora

Explanation:

In Spanish, "profesor" is a masculine - gendered noun referring to a male teacher. "pluma" (pen) is feminine, "cuaderno" (notebook) is masculine but not a human - related noun in the context of gendered nouns like the others here, and "maestra" is a feminine noun for a female teacher.

Answer:

profesor