Which of the following is a type of lower urinary tract infection?

A lower urinary tract infection typically refers to infections that occur in the bladder and urethra. Both types of infections are categorized under lower urinary tract infections. A bladder infection, also known as cystitis, occurs when bacteria infect the bladder, leading to symptoms such as frequent urination, urgency, and pelvic discomfort. Urethritis, on the other hand, is an infection caused by bacteria that inflames the urethra, which is the tube that carries urine out of the body.

Since both bladder infections and urethritis fall under the umbrella of lower urinary tract infections, the correct choice of both these conditions emphasizes that they are indeed types of lower urinary tract infections. A kidney infection, however, is a different condition classified as an upper urinary tract infection, affecting the kidneys rather than the lower tract, thus differentiating it from the other two. Therefore, the best answer is that both bladder infection and urethritis are considered types of lower urinary tract infections.