Introduction:
In organic chemistry, the stability of an alkene is determined by several factors, including the presence of conjugation, the nature of substituents, and the degree of substitution. In this question, we are comparing the stability of three different alkenes: cis-2-butene, trans-2-butene, and 1-butene.

Explanation:
To determine the stability of these alkenes, we need to consider the following factors:

1. Degree of substitution:
The degree of substitution refers to the number of alkyl groups attached to the double bond carbon atoms. The more substituted the alkene, the more stable it is. In this case, cis-2-butene and trans-2-butene are both disubstituted alkenes, while 1-butene is monosubstituted.

2. Presence of conjugation:
Conjugation refers to the alternating pattern of single and multiple bonds in a molecule. It can provide stability to the molecule due to delocalization of π electrons. In this case, both cis-2-butene and trans-2-butene have a conjugated system, while 1-butene does not.

3. Steric hindrance:
Steric hindrance refers to the repulsion between atoms or groups due to their spatial arrangement. In this case, both cis-2-butene and trans-2-butene have similar steric hindrance since they have the same substituents (methyl groups) attached to the double bond carbon atoms.

Conclusion:
Based on the above factors, trans-2-butene is the most stable alkene among the given options. It is disubstituted, has a conjugated system, and experiences similar steric hindrance as cis-2-butene. On the other hand, cis-2-butene is less stable due to the presence of cis-steric strain caused by the bulky methyl groups on the same side of the double bond. 1-butene is the least stable among the options as it is monosubstituted and lacks conjugation.

Therefore, the correct answer is option B) Trans-2-butene.