Which description best matches the gross lung pathology seen with EMV?

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The main idea here is an acute inflammatory process in the lungs that causes vascular leakage and edema, with the lung attempting to clear it through the lymphatics. When a virus or similar infectious process inflames the lung tissue, the tiny blood vessels become leaky, leading to crowding of blood in the lungs (congestion) and the lungs feeling firm from edema and inflammatory exudate. The lymphatic vessels enlarge as they try to drain this excess fluid and debris, hence lymphatic dilation. The alveolar spaces fill with protein-rich fluid mixed with red blood cells from capillary damage, producing a foamy, hemorrhagic exudate. This combination of congested, firm tissue with enlarged lymphatics and foamy hemorrhagic exudate fits an acute, diffuse pneumonic pattern seen with EMV. It contrasts with normal lungs (no edema or exudate), emphysema (air-space destruction with hyperinflation), or fibrotic scarring (chronic, fibrous thickening), which do not match this acute, exudative picture.