Directions: In the following passage, some words have been deleted. Read the passage carefully and select the most appropriate option to fill in each blank.

If we look at the global population, out of every six persons living in this world, one is an Indian and (1)______ a Chinese. The population of Pakistan is very (2)_____ and accounts for roughly about one-tenth of China or India. Though China is the largest nation and geographically (3)____ the largest area among the three nations, its density is the lowest. Scholars point out the one child (4)____ in China in the late 1970s as the major reason for low population growth. They also state that this measure led to a (5)_____ in the sex ratio, the proportion of females per 1000 males.

Select the most appropriate option to fill in blank number 4.