The correct option is A <!--td {border: 1px solid #ccc;}br {mso-data-placement:same-cell;}-->
Chris said that he wanted to bring his guitar to school yesterday.
<!--td {border: 1px solid #ccc;}br {mso-data-placement:same-cell;}-->
As this sentence is reporting Chris' statement from the past, the verb form of 'want' should be in simple past tense, which is 'wanted'.