Another brave warrior in the army of the Kauravas, he shared his name with an elephant. He had acquired the most effective 'Astra' or weapon. Known as Brahmastra, the astra never failed. When it was aimed at a particular person that person was sure to die. In the battle he used it to kill Ghatotkach. Who are we referring to?

To solve this question, the user needs to know about the characters in the Indian epic Mahabharata and the weapons used by them.

The description in the question refers to a warrior who had the most effective weapon called Brahmastra, which never failed and was capable of killing the target. The warrior used it to kill Ghatotkach in the battle.

Let's go through each option to determine the correct answer:

A. Dhrishtadyumna: Dhrishtadyumna was the son of Drupada, the king of Panchala. He was the commander-in-chief of the Pandava army. There is no mention of Dhrishtadyumna possessing Brahmastra in the Mahabharata.

B. Bali: Bali was a monkey king who was killed by Lord Rama in the Ramayana epic. He is not a character in the Mahabharata.

C. Karna: Karna was a warrior on the Kaurava side who was known for his skills with the bow and arrow. He was also a friend of Duryodhana, the Kaurava prince. However, there is no mention of Karna possessing Brahmastra in the Mahabharata.

D. Ashwathama: Ashwathama was the son of Dronacharya, the guru of the Kauravas and the Pandavas. He was a powerful warrior who fought on the Kaurava side in the Kurukshetra war. He possessed the Brahmastra and used it to kill the sons of Pandavas while they were asleep. He is the only warrior in the Mahabharata who is known to have possessed Brahmastra, which is capable of killing the target. Therefore, the correct answer is:

The Answer is: D. Ashwathama