Questions

A devastating  series of earthquakes in 1906 ruined the city completely and its presence is a constant remainder of the past and a threat of repetition in future.

In the above options, sperms are the haploid cells. In humans, haploid cells are those have only half the number of usual number of chromosomes. Sperm, gamates and egg cells are the haploid cells examples.

The meanings of the given words are as follows:
Zealous: having or showing zeal
Droopy: hanging down limply
Gigantic: of very great size or extent; huge or enormous
Tenacity: the quality or fact of being able to grip something firmly; grip
Assiduity: constant or close attention to what one is doing
Fervent: having or displaying a passionate intensity
Apathetic: showing or feeling no interest, enthusiasm, or concern
Conceited: excessively proud of oneself; vain
Capacious: having a lot of space inside; roomy
Hilarity: extreme amusement, especiallywhen expressed by laughter
Livid: furiously angry
Therefore, it can be observed that option C i.e. ‘fervent, apathetic’ forms a synonym- antonym pair of ‘zealous’.

DNA is not a single stranded and does not have amino acids. Hence options, b & C are eiminated. Dna is a double helix structure containing nucleobase—either cytosine (C), guanine (G), adenine (A), or thymine (T)—as well as a monosaccharide sugar called deoxyribose and a phosphate group.