以下是科学家采用不同方法培育良种牛的过程，a﹣h为操作过程，请据图回答有关问题：

（1）图中c的操作名称是____ ，d、f的操作名称是____ ．

（2）图中用到的激素是____ ，其目的是获得更多的卵母细胞，其受精后发育可得到早期胚胎；图中早期胚胎属于胚胎发育的____ 期，其中胚胎干细胞来源于____ （填数字标号）．

（3）过程h常用的方法是____ ．采用____ 技术来检测转基因牛D的DNA上是否插入了目的基因．

（4）图中牛A、B的性别____（填“相同”、“不相同”、“不一定相同”）

Dear Grandma and Grandpa,

    I miss you so much. Thank you for the new bike! I'm so excited! How did you know 1 is my favorite color?

    When I first 2 the box under the Christmas tree, I didn't know what it was. I thought it was 3 small to hold a bike. Then when I opened it, I saw that the bike was in small pieces. That's 4 the box was small!

    Dad and I put them 5 the next day. It was a lot of fun. 6 we finished, I got on the blue bike and 7 around the town. My old bike was too small for me. This one is just 8. It looks great, too! All 9 friends want one like this now. Dad said that I could take my 10 when we go to visit you in the spring. I can't wait.

Yours,

David