Final answer:
The first tissues that will become the human embryo's gonads begin to develop during the fetal period, specifically from 9 to 12 weeks after fertilization. The correct answer to the question is option 2) 9 to 11 weeks.
Step-by-step explanation:
Human Embryo Gonadal Development
The first tissues which will become the human embryo's gonads begin to develop during the embryonic stage, particularly in the fetal period starting from the ninth week of gestation until birth. Thus, the gonads start their differentiation within the period of 9 to 12 weeks after fertilization. This is a phase when sexual differentiation occurs, and in which embryonic males and females that are genetically distinguishable, appear morphologically identical with bipotential gonads.
During the initial stages of development, namely the pre-embryonic and the embryonic stages which take place from fertilization up to the eighth week, there is a focus on cell division, migration, and differentiation. Organ formation is another key developmental stage that occurs between weeks 4 and 8, during which the major organs begin to form. However, the differentiation into male or female gonads does not take place until the fetal stage.
Therefore, the correct answer to the question about the period in which the first tissues of the human embryo's gonads develop is option 2) 9 to 11 weeks.