The sentence that contains an unnecessary shift in verb tense is the second one - Lee noticed a problem and alerts a teacher.
It should be <em>alerted, </em>which is the past tense as the first verb <em>noticed.</em>
Answer: B is your answer.. I know it can never be the last two.
The answer is... In hazardous situations, the instinct to survive overcomes everything else.
On the one hand, <u><em>your</em></u> is a possessive and means that something belongs or is related to "you", whoever that subject is. On the other hand, <em><u>you're</u></em> is a contraction. It is short for "you are" that includes the personal pronoun <em>you</em> and the conjugated verb <em>to be</em>. Therefore, the sentence that accurately uses the homophones "your" and "you're" is: Don’t forget to pick up your homework before you leave.