Arrange the following reginal trade blocks on the basis of number of member Nations in descending order.

A. North American Free Trade Association (NAFTA)
B. EU (European Union)
C. OPEC (Organisation of Petroleum Exporting Countries)
D. SAFTA (South Asian Free Trade Agreement)

Choose the correct answer from the options given below:

B, C, D, A

The correct answer is Option (4) → B, C, D, A

B. EU (European Union)- Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Netherlands and United Kingdom (29)

C. OPEC (Organisation of Petroleum Exporting Countries)- Algeria, Indonesia, Iran, Iraq, Kuwait, Libya, Nigeria, Qatar, Saudi Arabia, U.A.E. and Venezuela (11)

D. SAFTA (South Asian Free Trade Agreement)- Bangladesh, Maldives, Bhutan, Nepal, India, Pakistan and Sri Lanka (7)

A. North American Free Trade Association (NAFTA)- U.S.A, Canada and Mexico (3)