**Core Concept**
Erikson's theory of psychosocial development is a framework that describes eight stages of human development, each characterized by a unique conflict or crisis that must be resolved. The first stage, trust versus mistrust, occurs from birth to approximately one year of age and is crucial for establishing a sense of security and trust in the world.

**Why the Correct Answer is Right**
Erik Erikson, a German-American psychologist, proposed the concept of trust versus mistrust as the first stage of his psychosocial development theory. During this stage, infants learn to trust their caregivers and the world around them, which lays the foundation for future relationships and emotional well-being. If caregivers respond to the infant's needs in a consistent and nurturing manner, the infant develops a sense of trust, whereas inconsistent or neglectful care can lead to mistrust.

**Why Each Wrong Option is Incorrect**
**Option A:** Seligman, an American psychologist, is known for his work on learned helplessness and positive psychology, but he did not propose the stage of trust versus mistrust.
**Option C:** Lorenz, an Austrian zoologist, is famous for his work on animal behavior, particularly imprinting, but his research does not relate to human psychosocial development.
**Option D:** Bleuler, a Swiss psychiatrist, is best known for his work on schizophrenia, introducing the term "autism" to describe its symptoms, but he did not contribute to Erikson's theory of psychosocial development.

**Clinical Pearl / High-Yield Fact**
Erikson's stages of psychosocial development provide a framework for understanding human development and the potential consequences of unresolved conflicts or crises at each stage. Remembering these stages can help clinicians identify potential areas of growth or challenge for patients across the lifespan.

**✓ Correct Answer: B. Erikson**