Choose the best way to revise sentence 12 to create parallel structure h

O Doing some of the problems in my head, writing the last answer,
and stopping writing when the bell rang.
O I did some of the problems in my head, wrote the last answer, and
stopped writing when the bell rang.
nd
ar
ED
Some of the problems I did in my head, writing the last answer, and
stopping writing when the bell rang.
o I did some of the problems in my head, write the last answer, and
stop writing when the bell rang.

The correct answer is B. I did some of the problems in my head, wrote the last answer, and stopped writing when the bell rang.

Explanation

Sentence # 12 "I did some of the problems in my head, the last answer I wrote, and when the bell rang I stopping writing" needs to be revised because it does not have a parallel structure "did", "wrote" and "stopping". To review this sentence to create a parallel structure it is necessary to change the last verb "stopping" to "stopped" to maintain the parallel structure which establishes one verbal tense. Moreover, the best tense is simple past because the author was talking about an past event. According to the above, the correct answer is B.

kenny´s more than 25 years of relevant public service. in the army for two decades, as official representative for four years, and now for the department of state, as ambassador. this career clearly demonstrates great capacities in the public sector.