Who has been sent to the Senate by the US as the director of the Bureau of Consumer Financial Protection?

In the following passage some of the words have been left out. Read the passage carefully and choose the correct answer to each question out of the four alternatives and fill in the blank.

The Solar System has been a complicated wonder for the astronomers. This is a__(21)__to which we may never have the exact answer. Man has wondered__(22)__the age of the Earth__(23)__ ancient times. There were all kinds of__(24)____that seemed to have the___(25)___But man could not begin to think about the question scientifically until about 400 years ago when it was proved that the Earth revolved round the Sun and the Earth was a part of our Solar System, then scientists knew where to begin. 

Fill at the option (25).

The marshy gas which is produced on decomposition of organic matter and is mostly found in coal mines, is the name of that gas?

Direction: In the following question, out of the four alternatives, choose the one which can be substituted for the given sentence.

One who travels by foot

Which one of the following Mountain Peak is not located in Sirohi District? 

Based on the relationship between the first two words, find out the missing word.
BHARATANATYAM : TAMILNADU  ::  KUCHIPUDI: ?

Which of the following is not a simple tissue?

Which University in London has developed a potential COVID-19 vaccine and the first human trials will begin from April 23, 2020?