G-chem: Electrochemistry?

[2hotinhere]

Hi, I am doing hw, and I got this question wrong, I don't understand why i got it wrong. Can someone help me understand why the correct answer is right?
I read the explanation but still do not understand.

The standard potential for the reaction K+ + e– K(s) equals –2.93 V. If solid potassium is placed into an aqueous solution of HCl, then:

A. H2(g) and KCl(aq) are produced.

B. Cl2(g) and KCl(aq) are produced.
C. Cl2(g), H2(g), and KCl(aq) are produced.
D. no reaction occurs.

Explanation: [correct answer is A]
(book explanation)
A. Since the reduction of K+ as given in the question has a negative potential, the oxidation of K(s) to K+ will have a positive potential and be spontaneous. This eliminates choice D. Hydrochloric acid (HCl, a strong acid) will dissociate nearly completely in water into H+ and Cl–. In the presence of a reducing agent (K), H+ ions can accept electrons and be reduced to H2, and K+ and Cl– will remain in solution. Since there is no oxidant which can accept the extra electron from Cl–, Cl2 will not be formed, eliminating choices B and C.

--Can someone make sense of why does H2 bond with each other? what does the reduction of K has to do with H2 bond?

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[funtertaining15]

It might help to write out the rxn:
K+ HCl==> KCl + H

K goes from o-->+1, so it is getting oxidized
H goes from +1-->0, so it is being reduced...
Cl's oxidation potention dosn't change....
K will at at as a reduing agent and "reduce" H, so it will accept electrons, and thus have an oxidation of 0. H's elemental form, H2 has it's oxidation number at O, so I guess that's why.
balanced form :
2K + 2HCl---> 2KCl +H2.....I think