Abiotic and biotic factors of a meadow

Q: a pair of homologous chromosomesa) always has the same genes and the same allows b)always has the same genes c)always has the same alleles d)never has the same genes

Could someone me with number one you

How does the molecular clock work? a. it analyzes the brain functionality of two different species.b. it examines and compares the physical characteristics of two different species.c. it illustrates relationships between two different species.d. it compares the number of mutations that exist in the dna of two different species.