The most outstanding Rajput ruler in the post Aurangzeb period was Sawai Raja Jai Singh of Amber. He built the beautiful city of Jaipur. He also erected astronomical observatories at five places. At how many of the following places he did not erect these?

a. Banaras

b. Ujjain

c. Mathura

d. Udaipur

e. Allahabad