One common logical flaw that GMAT CR often presents is failing to account for other possibilities. Take this analogous argument:

Unless thieves keep stealing the inventory from my store, I will soon be broke and out of business. I have therefore decided to install a state-of-the-art security system and armed guards so that no one can steal anything from me. Therefore, my business will thrive.

This argument is clearly flawed: just because the business was threatened by thieves, that does not guarantee that the business will be successful once we remove the threat of thieves. There are many other factors to a business's survival: what it's selling and at what cost, the state of the economy, etc.

In your example, a similar principle is at play. Just because hunting is threatening the survival of tigers, that does not mean that we can assume that nothing else is threatening the survival of tigers. It's possible that even if the threat of hunting is removed, other threats might impede the survival of tigers: lack of habitat or food, disease, etc.

We need to find an answer choice that points out that the argument ignores all other possibilities.

(A) assumes without sufficient warrant that a ban on tiger hunting could be successfully enforced
This seems compelling, but consider the wording of the argument: "if these countries can successfully enforce this legislation, the survival of tigers in the wild will be ensured." The casual structure of the argument only concerns itself with cases in which the ban CAN be enforced. It is not declaring that that definitely WILL happen; only that if it does happen, the tigers will survive.

(B) considers the effects of hunting on tigers without also considering the effects of hunting on other endangered animal species
Other animals are irrelevant to the argument.

(C) fails to take into account how often tiger hunters are unsuccessful in their attempts to kill tigers
Irrelevant. The argument states that hunting threatens tigers, so we can assume that the hunters are successful often enough to be a threat.

(D) neglects to consider the results of governmental attempts in the past to limit tiger hunting
Whether there have been attempts in the past or not has no bearing on the logical soundness of this argument.

(E) takes the removal of an impediment to the tigers' survival as a guarantee of their survival
Exactly! Hunting threatens tigers, but that does not necessarily mean that no hunting = tigers will survive.

The answer is E.

Here are some other examples of CR arguments that failed to account for other possibilities:
https://www.beatthegmat.com/ledland-unem ... tml#716308
https://www.beatthegmat.com/weaken-olex- ... tml#564585
https://www.beatthegmat.com/princeton-re ... tml#717367
https://www.beatthegmat.com/firms-adopti ... tml#769255