Explanation:

First option is correct i.e. The name BrahMos is a portmanteau formed from the names of two rivers which are the Brahmaputra of India and the Moskva of Russia

Brahmos-

•     Supersonic cruise missile
•     Designed and developed by BrahMos Aerospace, a joint venture of India and Russia
•     It operates on fire and forget principal
•     Capable of being launched from land, sea, sub-sea and air against sea and land targets
•     Carrying capacity : 300 Kg (both conventional and nuclear)
•     Speed : Mach 3 (that is, three times the speed of sound)
•     Max Range : 290 Km. Its range was extended to 450 km and plan is to increase it to 600km.
•     It is two-stage missile, the first one being solid and the second one ramjet liquid propellant.
•     BrahMos missile already has been inducted into the Indian Army and Navy