Which sentence contains an inappropriate shift in verb tense?

Responses

Medicine continued to make remarkable advances in the 20th century, as technology entered the operating theater and new antibiotics became available.
Medicine continued to make remarkable advances in the 20th century, as technology entered the operating theater and new antibiotics became available.

Medicine makes remarkable advances in the 20th century, as technology entered the operating theater and new antibiotics become available.
Medicine makes remarkable advances in the 20th century, as technology entered the operating theater and new antibiotics become available.

Medicine continues to make remarkable advances as technology enters the operating theater and new antibiotics become available.
Medicine continues to make remarkable advances as technology enters the operating theater and new antibiotics become available.

Medicine made remarkable advances in the 20th century, as technology entered the operating theater, and new antibiotics became available.

Medicine made remarkable advances in the 20th century, as technology entered the operating theater, and new antibiotics became available.

The sentence that contains an inappropriate shift in verb tense is:

Medicine makes remarkable advances in the 20th century, as technology entered the operating theater and new antibiotics become available.

In this sentence, the shift from past tense ("entered," "became") to present tense ("makes," "become") is inappropriate. The correct tense should be consistent throughout the sentence, either past or present.

The sentence that contains an inappropriate shift in verb tense is:

"Medicine made remarkable advances in the 20th century, as technology entered the operating theater, and new antibiotics became available."

In this sentence, the verb tense shifts from the present tense "continues" and "enters" to the past tense "made" and "became." The verb tense should remain consistent throughout the sentence.