Answer:
observation because you are using senses such as sight and smell to come to a logical conclusion about something.
Correct answer:
"<span>B- homologous chromosomes join together to form tetrads during prophase I"
</span>It is during prophase I that homologous chromosomes join together (<span>synapsis)</span> and form tetrads - four chromatids are together in the new structure of two chromosomes - and this is the reason why crossing-over occurs in this phase. It is in this tetrad that both arms of both chromosomes may crossover and matching regions exchange places. This process results in homologous chromosomes recombination leading to genetic variability.
The skeletal system<span> performs vital </span>functions<span>— support, movement, protection, blood cell production, calcium storage and endocrine regulation — that enable us to survive.</span>
I guess it will be C: atoms and molecules because according to Jhon Dalton's
atomic theory :"all matter is made up of atoms"
and even if we think of other options think it by urself that not all matter is made up of them
