Answer: Option (3) is the correct answer.
Step-by-step explanation:
Atomic number of lithium is 3 and atomic number of bromine is 35. So, lithium has one extra electron whereas bromine has deficiency of one electron according to the octet rule.
Thus, when lithium combines with bromine then it results in the formation of ionic bond. That is, bond formed by transfer of electrons is known as ionic bond.
Thus, lithium loses one electron and becomes a positively charged ion.