I say b and d because they both indicate about the heart
Yes because type O blood is the universal donor.
<em>Direct </em><em>Contact</em><em> </em><em>Infection</em>
<em>Direct</em><em> contact are touching, kissing, contact with oral secretions, or contact with body lesions.</em>
<em>Hope</em><em> </em><em>it</em><em> </em><em>helps</em><em> </em><em>(⌒▽⌒)</em><em>(⌒▽⌒)</em>
Its either dead material or organisms that eat producers