Answer:
A. volcanic ash layers were regularly interspersed between the sedimentary strata.
Explanation:
The discovery of a fossil is a moment of accomplishment for archaeologists, hence the date dating process begins and the older the relic the greater its value for paleontology. Chemistry is present in this process, more precisely the carbon element, but other elements can be used as uranium, lead, potassium and argon.
In the case of the fossils reported in the question, to assign absolute dates to fossils in this sediment core would be most useful if volcanic ash layers were regularly interspersed between sedimentary strata because it would separate sedimentation times and allow the use of more than one element. dating, making the search more complete and the date most credible.
The X symbol looks too much like the multiplication symbol, it also makes using it as a variable more confusing.
Adaptation because organisms adapt to avoid extinction.
Transformation is the genetic alteration of a cell resulting from the direct uptake of incorporation of exogenous genetic material from its surrounding through the cell membrane.
If you have one sickle cell gene, you have sickle cell trait and you will not develop the sickle cell disease. If you inherit two sickle cell genes, you have sickle cell anemia.
