**Core Concept**
The human sexual response cycle is a complex process that involves various physiological and psychological changes. It consists of four phases: excitement, plateau, orgasm, and resolution. This question requires understanding of the physiological changes that occur during these phases, particularly in males.

**Why the Correct Answer is Right**
The correct answer is during the **resolution phase**. During this phase, the body returns to its pre-intercourse state, and it is physiologically impossible for males to achieve erection or orgasm. This is because the parasympathetic nervous system is deactivated, and the sympathetic nervous system takes over, leading to a decrease in blood flow to the penis and a decrease in testosterone levels. Additionally, the resolution phase is characterized by a decrease in oxytocin and vasopressin levels, which are essential for ejaculation and orgasm.

**Why Each Wrong Option is Incorrect**
**Option A:** The excitement phase is characterized by increased blood flow to the penis, leading to an erection. It is possible for males to achieve erection or orgasm during this phase.
**Option B:** The plateau phase is a state of heightened sexual arousal, and males can still achieve erection or orgasm during this phase.
**Option C:** Orgasm is a specific phase of the sexual response cycle, and it is not the phase during which it is physiologically impossible for males to achieve erection or orgasm.

**Clinical Pearl / High-Yield Fact**
It is essential to note that premature ejaculation is a condition where males experience orgasm or ejaculation before they desire it, which can occur during the excitement or plateau phase. This condition is often treated with selective serotonin reuptake inhibitors (SSRIs) or other medications that delay ejaculation.

**Correct Answer:** D. Resolution