A.I. Explanation:

Option 1: "The motivation behind alien plunders visiting Earth is to know more about Human technology."

Explanation: This option is incorrect because the text states that the purpose of alien visitors, as suggested by Stephen Hawking, was to send one-way colonists to augment their race, not to learn about human technology.

Option 2: "The chances of aliens visiting Earth multiple times is rare."

Explanation: This statement is incorrect as the text indicates that the scenario of aliens visiting Earth is likely to happen more than once, contradicting the idea of rarity.

Option 3: "Laws of Physics apply throughout the universe and that might help humans create a better defense mechanism against space invaders."

Explanation: This option is correct because the text mentions that Earth's hope in defense relies on the applicability of the laws of physics across the universe, suggesting that understanding these laws could aid in developing defense mechanisms.

Option 4: "Speculation about the future is termed as fiction."

Explanation: This statement is correct as the text explicitly defines speculation about futurity as fiction, aligning perfectly with the content presented.

Option 5: "The report released after carrying out the study included details of the frequency of acid rain."

Explanation: This option is incorrect because there is no mention of a report or acid rain in the text, making this information not present.