After reviewing the research findings, I would choose **TSMC** as the best company for investment.

## Why TSMC was chosen

TSMC stands out as the strongest overall investment choice because it combines:

- **A dominant market position**: It is the leading global foundry and sits at the center of the semiconductor supply chain.
- **Direct exposure to AI growth**: It benefits from rising demand for advanced AI chips and is a critical manufacturing partner for many of the world’s most important chip designers.
- **Strong future outlook**: The company expects **more than 30% sales growth in 2026**, which signals durable demand and strong execution momentum.
- **High-quality long-term moat**: Its manufacturing scale, technological leadership, and customer diversification make it one of the most defensible ways to invest in the AI infrastructure buildout.

TSMC is especially attractive because it gives investors exposure to AI growth without relying on a single product cycle or a narrow customer story. It is a foundational business in the AI ecosystem, which makes its earnings base more resilient than many higher-beta AI names.

## Why the other companies were not selected

### Broadcom
Broadcom is a strong AI beneficiary and has impressive AI semiconductor growth, but I did not choose it because:
- Much of the AI optimism may already be reflected in the stock after a major run-up.
- It faces valuation risk and margin pressure.
- It is compelling, but less attractive than TSMC on a risk-adjusted basis.

### AMD
AMD has an appealing growth story and real upside in AI and data center computing, but it was not selected because:
- It faces stronger competitive pressure from larger rivals.
- Its AI opportunity is promising, but still more execution-dependent.
- It is a higher-volatility choice than TSMC.

### Cerebras
Cerebras was not selected because:
- It is still early in its public-market journey.
- It has far less proven financial and commercial scale than the established leaders.
- The stock carries substantial execution and valuation risk.

### Arm Holdings
Arm is interesting because of its dominant architecture role and potential expansion into AI chips, but it was not selected because:
- Its new AI chip strategy is still unproven.
- Moving deeper into hardware adds execution complexity.
- The investment case is strong, but more speculative than TSMC’s.

### Samsung Electronics
Samsung is well positioned in AI memory, but it was not selected because:
- Its business is less focused than TSMC’s pure AI infrastructure exposure.
- Memory markets are historically cyclical.
- Although it has upside, the risk profile is less attractive than TSMC’s combination of leadership and demand visibility.

## Final decision

**Selected company: TSMC**

**Reason:** It offers the best combination of AI exposure, industry leadership, durable competitive advantage, and visible long-term growth, while avoiding some of the valuation and execution risks that affect the other candidates.