Groundwater supplies can be easily contaminated by surface mining of coal All BUT ONE may be how surface mining might adversely affect groundwater conditions,

A)
direct dumping of tailings and effluents into rivers

B)water used in the chemical extraction of metals, commonly contains
process chemicals

C)water which has trickled through solid mine wastes may contain dissolved
minerals, process chemicals, and/or metals

D)technologies used to control water flow prevents contamination

answer: option (b) is the correct answer.

explanation:

a covalent bond is formed by sharing of electrons. whereas polarity arises due to difference in electronegativity of two atoms.

therefore, more is the electronegativity of an atom which combines with the titanium, more readily it will induce a partial positive and negative charge.

thus, out of the given options fluorine is most electronegative and has an incomplete octet. therefore, it will readily combine with titanium to share the electrons and complete its octet.  

one negative thing it that it can kill water animals. another negative thing is it can cause the destruction of ecosystem. one way water pollution can be reduced is to conserve energy.