The scientific name of the housefly is Musca domestica. According to the rules of binomial nomenclature, the genus name (Musca) should be capitalized, and the species name (domestica) should be lowe

The scientific name of the housefly is Musca domestica. According to the rules of binomial nomenclature, the genus name (Musca) should be capitalized, and the species name (domestica) should be lowercase. The entire name should be italicized or underlined.

Comparing the options:

• (A) Musca Domestica: Species name is capitalized, which is incorrect.
• (B) Musca Domestica (underlined): Species name is capitalized, which is incorrect.
• (C) Musca domestica: Correct capitalization, but not underlined or italicized.
• (D) Musca domestica (underlined): Correct capitalization and correctly underlined.

Therefore, option (D) is the most accurate representation of the scientific name.

The final answer is $\boxed{\text{D}}$