B - Atomic number. Dmitri Mendeleev organised the table according to atomic weight, however this caused problems with elements such as iodine and tellurium, Iodine has a higher mass, but a lower atomic number. And to make iodine in the same group as similar elements (halogens), Mendeleev had to break his own rules and put it before tellurium in the table. Moseley fixed this problem by ordering the elements according to atomic (proton) number.
Answer:
The decreasing order of bond length in the carbon - carbon bonds will be:

Explanation:
Bond length is defined as average distance between two nuclei of bonded atoms in a molecule.Bond length is inversely proportional to the number of bonds present between two atoms.
...[1]
Bond energy is defied as amount of energy required to break apart the bond of 1 mole of molecule into their individual atom. Bond energy is directly proportional to the number of bonds present between two atoms.
..[2]
From [1] and [2]:

hybridized
hybridized
hybridized
Extent of overlapping of orbitals in these hybridization;

Higher the overlapping of orbital more closer will be both atoms to each other and shorter will be the bond lenght.
So, the decreasing order of bond length in the carbon - carbon bonds will be:

Like flowing water, flowing ice erodes the land and deposits the material elsewhere. Glaciers cause erosion in two main ways: plucking and abrasion.
Plucking is the process by which rocks and other sediments are picked up by a glacier. They freeze to the bottom of the glacier and are carried away by the flowing ice.
The other way you'll need more informations because my Knowledges are limited by here.