To solve this problem, we need to identify which components are fused in somatic hybridization involving two varieties of plants.$\newline$Let's analyze each option:$\newline \bullet$Option 1: Protoplasts$\newline$ - Protoplasts are plant cells with the cell wall removed.$\newline$ - In somatic hybridization, protoplasts from different plant varieties are fused to combine their genetic material.$\newline$ - This fusion allows for the creation of hybrid plants with desirable traits from both parent varieties.$\newline$ - Therefore, protoplasts are indeed fused in somatic hybridization.$\newline \bullet$Option 2: Pollens$\newline$ - Pollens are involved in sexual reproduction and are not used in somatic hybridization.$\newline$ - Somatic hybridization is a form of asexual reproduction and does not involve pollens.$\newline \bullet$Option 3: Callus$\newline$ - Callus is a mass of undifferentiated plant cells.$\newline$ - While callus can be used in tissue culture, it is not directly involved in the fusion process of somatic hybridization.$\newline \bullet$Option 4: Somatic embryos$\newline$ - Somatic embryos are formed from somatic cells and are not involved in the initial fusion process of somatic hybridization.$\newline$ - They may be used later in the development of plants from the fused protoplasts.$\newline$Based on the analysis, the correct answer is Option 1: Protoplasts.$\newline$This corresponds to the correct option, which is Option 1.