521: Which one of the following plants is effective in reducing water pollution and is also useful for producing bio gas ?

(a) Eucalyptus

(b) Water hyacinth

(c) Salvinio

(d) Lotus
522: Roman settlement in India is found at

(a) Ujjain

(b) Kshudrakas

(c) Arikmedu

(d) Koshambi
523: Which of the following statements regarding the Constituent Assembly are true?

I. It was not based on adult franchise.

II. It resulted from indirect elections.

III. It was a multi-party body.

IV. It worked through several committees.

Select the correct answer from the codes given below.

Codes:

(a) I and II

(b) II and III

(c) I and IV

(d) I, II, III and IV
524: Match the following research institutes A, B, C and D with their respective location labelled as 1 to 6 in the given rough outline map

A. Central Drug Research Institute
B. National Atlas and Thematic Mapping Organisation
C. National Institute of Ocean Technology
D. Temperate Forest Research Centre

Select the correct answer using the codes given below :

Codes:

(a) A-4, B-3, C-2, D-6
(b) A-4, B-5, C-1, D-6
(c) A-2, B-3, C-4, D-5
(d) A-1, B-6, C-2, D-3
525: "Black holes" refers to

(a) Holes occurring in heavenly bodies

(b) Bright spots on the sun

(c) Collapsing object of high density

(d) Collapsing object of low density