Answer is A.. hope this helps:)
Ammonoids are good as index fossils because of the following characteristics;
<span>1.
</span>Their abundance and vast distribution across most shallow
marine waters during the periods
<span>2.
</span>They have easily recognizable
features, such as shells and the highly crenulated and complex suture, that are well preserved in rocks
<span>3.
</span>Their rapid
evolution that can assist determine changes and variations in the then environment
It can be multiple hits to the head over time.
False
Symbiotic relationship would be a mutuality of organisms where the other shares a deep physiological and psychological share of individuality.
<span>There are several types of biotic relationships that is occurring every single moment in the ecosystem and one is parasitism. In this scenario with human beings and mosquitos, this phenomenon of interaction is distinguished as parasitism where mosquitos draws blood that contains nutrients from the human tissue to use it as its source of food and then leaves harmful substances and bacteria in the human’s blood stream. </span>
