Answer: a. It receives a hydrogen ion.
Explanation: Base is a species which is capable of donating its negative quantity and accepting the positive one.
For example, ammonia is considered as a base because it is capable of donating its lone pairs of electrons and can accept an proton as well.
Here, out of the given options, Hydrogen 
is a proton which is acting as a positive species and hydroxide ion 
is a negative species.
Thus, option (A) is the correct answer as it will receive a hydrogen ion from another base making itself a conjugate acid.
<span>3. relate to properties of elements and how they may react.
Periodic trends are specific patterns that are present in the periodic table that include size, electronic properties, melting point, electronegativity and metallic character. The trends exist due to the similar atomic structure of the elements within each group family.</span>
Answer:
They may have different phenotypes because of differences in their environments, such as nutrition and healthcare. Why might genetically identical twins have different phenotypes? Any genes on the same chromosome could be linked genes, whereas only genes on sex chromosomes can be sex-linked genes.
Explanation:
Taking into account the definition of density, assuming all other conditions remain the same, increasing mass will cause an object's density to increase.
Density is defined as the property that matter, whether solid, liquid or gas, has to compress into a given space. That is, density is a quantity referred to the amount of mass contained in a given volume.
Density is an intensive property since it does not vary with the amount of substance.
Since density is the relationship between the mass and the volume of a substance, its calculation is defined as the quotient between the mass of a body and the volume it occupies:
In the previous expression it can be observed that the density is inversely proportional to the volume: the smaller the volume occupied by a certain mass, the greater the density.
On the other hand, density is directly proportional to mass: the greater the mass, the greater the density.
Finally, assuming all other conditions remain the same, increasing mass will cause an object's density to increase.
Learn more about density:
I think it would be C) The surrounding soil can become very fertile
