Select the option that contains a grammatical error in the underlined portion.

When Mrs. Sinha came to see Varanasi in 2019, Nupur has already been teaching there for five years.

A

When Mrs. Sinha came to see Varanasi in 2019, Nupur has already been teaching there for five years.

B

When Mrs. Sinha came to see Varanasi in 2019, Nupur has already been teaching there for five years.

C

When Mrs. Sinha came to see Varanasi in 2019, Nupur has already been teaching there for five years

D

When Mrs. Sinha came to see Varanasi in 2019, Nupur has already been teaching there for five years.