The number of candidates selected from Haryana during the period under review is approximately what percent of the number selected from Delhi during this period?

As per given graph in question,
The average production of 1990 and 1991 = (40 + 60)/2 = 100/2 = 50
The average production of 1991 = 60
Solve one by one option.
(A) The average production of 1991 and 1992 = (60 + 45)/2 = 105/2 = 52.5
(B) The average production of 1992 and 1994 = (45 + 50)/2 = 95/2 = 47.5
(C) The average production of 1993 and 1994 = (65 + 50)/2 = 115/2 = 57.5
(D) The average production of 1994 and 1995 = (50 + 75)/2 = 125/2 = 62.5

All the given option doesn't have average production of 50. So answer will be none of these.

Difference in the production of food-grains between 1991 and 1994 = Production of food-grains in 1991 - Production of food-grains in 1994
Put the value by seeing the graph
Difference in the production of food-grains between 1991 and 1994 = ( 60 ? 50 ) x 1000 = 10 x 1000 = 10,000

Check given option one by one.
Option (A),
Percentage increase in production in 1991 = {(Production in 1991 - Production in 1990)} x 100 % / Production in 1990
Percentage increase in production in 1991 = {( 60 - 40 )} x 100 % / 40
Percentage increase in production in 1991 = 20 x 100 % / 40
Percentage increase in production in 1991 = 100 % / 2 = 50 %
Option (B)
Percentage increase in production in 1993 = {( Production in 1993 - Production in 1992 )} x 100 % / Production in 1992
Percentage increase in production in 1993 = {( 65 - 45 )} x 100 % / 45
Percentage increase in production in 1993 = 20 x 100 % / 45
Percentage increase in production in 1993 = 4 x 100 % / 9 = 400/9 = 44.44 %
Option (C)
Percentage increase in production in 1995 = {( Production in 1995 - Production in 1994 )} x 100 % / Production in 1994
Percentage increase in production in 1995 = {( 75 - 50 )} x 100 % / 50
Percentage increase in production in 1995 = 25 x 100 % / 50
Percentage increase in production in 1995 = 100 % / 2 =50 %
Option (D)
Percentage increase in production in 1990 = {( Production in 1990 - Production in 1989 )} x 100 % / Production in 1989
Percentage increase in production in 1990 = {( 40 - 25)} x 100 % / 25
Percentage increase in production in 1990 = 15 x 100 % / 25
Percentage increase in production in 1990 = 15 x 4 % = 60 %