Ionic bonds result when electrons are tranfered between atoms. Covalent bonds result when valence electrons are shared between atoms. You should be able to identify whether an ionic or covalent bond is being formed between atoms.
The correct answer is A. Decline in vision
Explanation:
The term "middle age" is used to describe the time span between 45 and around 65 in human life. During this, important changes occur in terms of senses, this age usually implies a decline in senses including pain, taste, smell, and vision. In terms of vision, it is common during middle ages people began experiencing blurring vision or weakened vision as during this age conditions such as presbyopia, glaucoma, cataracts, among others. Additionally, the decline in vision in this age is commonly related to other conditions such as diabetes, the use of medicines and also jobs that are visually demanding. Thus, in middle age, people commonly experience a decline in vision.
Probably Mary's doctor will not doctor a chronic villus sampling because of her first time pregnancy at the aged of 37 and her doctor ordered so many series of routine screening procedure. The doctor will not order a chronic villus sampling on Mary.
Membrane is the answer i think