To solve this problem, we need to understand the structure of a typical angiosperm embryo sac at maturity.$\newline$The embryo sac is the female gametophyte in flowering plants and is crucial for reproduction. Let's analyze its structure:$\newline \bullet$The mature embryo sac is typically 8-nucleate and 7-celled.$\newline \bullet$It contains:$\newline$ - Three antipodal cells at the chalazal end.$\newline$ - Two synergid cells and one egg cell at the micropylar end, forming the egg apparatus.$\newline$ - One central cell with two polar nuclei, which eventually fuse to form a diploid secondary nucleus.$\newline$ - The total number of nuclei is 8, but the number of cells is 7 because the central cell contains two nuclei.$\newline$Therefore, the correct description of a typical angiosperm embryo sac at maturity is:$\newline$8-nucleate and 7-celled.$\newline$This corresponds to Option 1.