I think the correct answer from the choices listed above is option B. You can find methanogens in the human intestines. These organisms can work with or without oxygen. Too much of oxygen for them is toxic. They are obligate anaerobes.
The correct answer is tympanometer. A tympanometer is not used to measure hearing, but to rather measure the transmission of energy through the middle ear. In this way, tympanometry is an objective test of the function of the middle-ear. Tympanometry is used alongside other measures to asses hearing, such as pure tone audiometry.
The number 45 means that the subject has 44 normal autosomal chromosomes (22 chromosomes pairs) plus one (1) good sex chromosome (out of the normal homologous pair). The X0 means that the subject, usually a female, lacks one sister chromosome of the homologous X chromosome pair, or has a partial X sister chromosome.
In much of a digestive tract such as the human gastrointestinal tract, smooth muscle tissue contracts in sequence to produce a peristaltic wave, which propels a ball of food (called a bolus while in the esophagus and upper gastrointestinal tract and chyme in the stomach) along the tract.
