Consider the following techniques/phenomena : 1. Budding and grafting in fruit plants 2. Cytoplasmic male sterility 3. Gene silencing Which of the above is/are used to create transgenic crops?

Transgenic crops are genetically modified crops that contain DNA from an outside source, i.e., foreign genes have been introduced into their genome. This typically involves modern molecular biology techniques. Let's analyze the given techniques: Budding and grafting in fruit plants: These are traditional horticultural techniques of vegetative propagation. They involve joining parts of two plants (scion and rootstock) to grow as a single plant. They do not involve the introduction of foreign DNA into the plant's genome and, therefore, do not create transgenic crops. They are used for combining desirable traits or propagating specific varieties. Cytoplasmic male sterility: Cytoplasmic male sterility (CMS) is a genetic trait that prevents the production of viable pollen. While CMS can occur naturally, it is also a trait that can be introduced or manipulated through various genetic engineering techniques (e.g., protoplast fusion, or sometimes via gene insertion into mitochondrial DNA) to facilitate hybrid seed production efficiently. In the context of creating modified crops, especially for commercial hybrid lines, its manipulation often involves advanced breeding or genetic engineering approaches to transfer these cytoplasmic genes. Gene silencing: Gene silencing (e.g., through RNA interference or using CRISPR-Cas9 technology) is a powerful molecular biology technique used to selectively reduce or switch off the expression of specific genes. This is a direct genetic engineering tool used to modify crop traits (e.g., enhancing disease resistance, altering nutritional content, or increasing shelf life) and thus creates transgenic crops. Given the options, cytoplasmic male sterility (when manipulated or transferred via advanced genetic methods) and gene silencing are techniques directly used or strongly associated with the creation of transgenic crops, while budding and grafting are purely conventional propagation methods.