Read the following sentence.

Sal and his brother had to mow the lawn, water the flowers and sweep the sidewalk before they could ride their bikes.

Which of these correctly edits the sentence for punctuation mistakes?

A) Sal and his brother had to mow the lawn, water the flowers, and sweep the sidewalk before they could ride their bikes.

B)Sal and his brother had to mow the lawn water the flowers and sweep the sidewalk before they could ride their bikes.

C) Sal and his brother had to, mow the lawn, water the flowers and sweep the sidewalk before they could ride their bikes.

D)Sal and his brother had to mow the lawn, water the flowers, and sweep the sidewalk, before they could ride their bikes.