सबसे तेज मैमोरी है?

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 (23).

TAT परीक्षण में कार्डो की संख्या कितनी होती हैं.

कांगड कांड किस प्रजामण्डल आन्दोलन में घटित हुआ?

नाभिकीय ऊर्जा प्राप्त करने हेतु आवश्यक है 

In the following question find out the correct spelling.

भारत के उच्चत न्यायालय द्वारा दिए गए निर्णय————— पर बाध्यकारी हैं।