Do recs HAVE to be related to prospective major?

<p>Hi, I'm a prospective Harvard applicant with strong interest in bio as a major (strong ec's, internships, etc.). Although my bio teacher likes me a lot, my AP US Hist teacher and AP Eng Comp teacher absolutely adore me and would write fantastic recs. Should I go with the US Hist and Eng teachers or make a slot for my bio teacher?</p>

<p>btw, I will probably have my research mentor write my supp rec.</p>