To solve this problem, we need to analyze the statements made by the Lion and the Unicorn and determine what day it is.
Let's go through each option and analyze the statements:
Option A) Wednesday - If today is Wednesday, then yesterday was Tuesday. According to the Lion, he lies on Mondays, Tuesdays, and Wednesdays. Therefore, if today is Wednesday, the Lion's statement would be false since he claims that yesterday was one of his lying days. However, if today is Wednesday, the Unicorn's statement would be true, as he tells the truth on Wednesdays. Since both statements cannot be simultaneously true, we can conclude that today is not Wednesday.
Option B) Thursday - If today is Thursday, then yesterday was Wednesday. According to the Lion, he tells the truth on Thursdays. Therefore, if today is Thursday, the Lion's statement would be true since yesterday was not one of his lying days. Additionally, if today is Thursday, the Unicorn's statement would be false, as he lies on Thursdays. Both statements can be simultaneously true if today is Thursday, so this option is a possibility.
Option C) Friday - If today is Friday, then yesterday was Thursday. According to the Lion, he tells the truth on Fridays. Therefore, if today is Friday, the Lion's statement would be true since yesterday was not one of his lying days. However, if today is Friday, the Unicorn's statement would also be true, as he tells the truth on Fridays. Both statements cannot be simultaneously true, so this option is not possible.
Option D) Sunday - If today is Sunday, then yesterday was Saturday. According to the Lion, he tells the truth on Sundays. Therefore, if today is Sunday, the Lion's statement would be true since yesterday was not one of his lying days. However, if today is Sunday, the Unicorn's statement would also be true, as he tells the truth on Sundays. Both statements cannot be simultaneously true, so this option is not possible.
Based on our analysis, we can conclude that the correct answer is option B) Thursday.