Small gram negative cocci, occur in pairs:

<p><strong><span>a- staphylococcus</span></strong></p> <p><strong><span>b- streptococcus</span></strong></p> <p><strong><span><span>c- neisseria</span></span></strong></p> <p> </p> <p><span><strong>d- non of the above</strong></span></p>