Definition: You are given a question or fill-in-the-blank question, two answer options (Option1 and Option2) and an Explanation. Your task is to find the correct answer (return the string of the correct option, not option1/2) for the given question from the given options and using explanation.

Positive Example 1 -
Input: Question: The government of Canada is considering implementing less carbon taxes across the country. If these taxes were implemented, the amount of carbon dioxide emissions in the country would be expected to 
 Option1: fall 
 Option2: rise 
 Explanation: The carbon taxes encourage people to use less fossil fuel, which reduces carbon dioxide emissions.
Output: rise

Positive Example 2 -
Input: Question: Shampoos with high ph are 
 Option1: less acidic 
 Option2: more 
 Explanation: Lower pH numbers are more acidic and higher numbers are less acidic (also called more alkaline).
Output: more

Negative Example 1 -
Input: Question: The government of Canada is considering implementing less carbon taxes across the country. If these taxes were implemented, the amount of carbon dioxide emissions in the country would be expected to 
 Option1: fall 
 Option2: rise 
 Explanation: The carbon taxes encourage people to use less fossil fuel, which reduces carbon dioxide emissions.
Output: fall

Negative Example 2 -
Input: Question: Shampoos with high ph are 
 Option1: less acidic 
 Option2: more 
 Explanation: Lower pH numbers are more acidic and higher numbers are less acidic (also called more alkaline).
Output: less acidic

Now complete the following example -
Input: Question: For dating the age of a fossil, and compared to the isotope Carbon 14 with its 5730 year half-life, would Francium with a 22 minute half-life be a 
 Option1: less useful isotope? 
 Option2: more useful isotope 
 Explanation: Because these isotopes decay more slowly, they can be used to date much older specimens.
Output: 


Answer: less useful isotope?