The first archaeologist who excavated Harappa, but could not recognize its significance, was:

A. Cunningham
Sir John Marshal
Mortimer Wheeler
George F. Dales

The correct answer is (a) A. Cunningham.

A. Cunningham was the first archaeologist to excavate Harappa, but he could not recognize its significance. He thought that it was a Buddhist monastery, and he did not realize that it was a major Indus Valley Civilization site.

Sir John Marshall was the second archaeologist to excavate Harappa. He was the one who recognized its significance as a major Indus Valley Civilization site.

Mortimer Wheeler was the third archaeologist to excavate Harappa. He continued the work that Marshall had started, and he made many important discoveries.

George F. Dales was the fourth archaeologist to excavate Harappa. He worked at the site in the 1960s and 1970s. He made many important discoveries, including the remains of a large city wall.

A. Cunningham was a British archaeologist who worked in India from the 1860s to the 1880s. He was the first archaeologist to excavate Harappa, in 1872. He thought that it was a Buddhist monastery, and he did not realize that it was a major Indus Valley Civilization site.

Sir John Marshall was a British archaeologist who worked in India from the 1890s to the 1930s. He was the second archaeologist to excavate Harappa, in 1920. He was the one who recognized its significance as a major Indus Valley Civilization site.

Mortimer Wheeler was a British archaeologist who worked in India from the 1940s to the 1960s. He was the third archaeologist to excavate Harappa, in 1946. He continued the work that Marshall had started, and he made many important discoveries.

George F. Dales was an American archaeologist who worked in India from the 1960s to the 1970s. He was the fourth archaeologist to excavate Harappa. He worked at the site in the 1960s and 1970s. He made many important discoveries, including the remains of a large city wall.