What can be said about the phylogeny of the early hominins? a. We do not have a secure, agreed upon phylogeny for early hominins, but we can still understand the general patterns of early hominin evolution. b. The absence of an agreed upon phylogeny of hominins makes it impossible to understand early hominin evolution. c. The most obvious pattern indicated by early hominin evolution is the early increase in brain size and slowing down of maturation rates. d. Only recently have we developed a secure and agreed upon phylogeny of early hominins.

Option A

Explanation:

Earlier it was believed that the human teeth especially the canines were a distinguishing factor for determining whether as species belongs to the family of humans or not. But only apes used to have such teeth but not the hominids and hence later on bipedalism (upright walking on rear limb) was considered as distinguishing factor.  

However, it was later recovered that certain other characteristics such as larger brains,  behavioral characteristics  etc, also distinguished hominins from other primates

Hence, there exists no agreed upon phylogeny for early hominins but general patterns of early hominin evolution can be understood.

Option A is correct

the overall balanced equation

6co2 + 6h2o > c6h12o6 + 6o2

sunlight energy

where: co2 = carbon dioxide

h2o = water

light energy is required

c6h12o6 = glucose

o2 = oxygen